Peptide Reference Desk
Is Dulaglutide a peptide? Why “GLP-1/Fc fusion protein” is the better answer
Dulaglutide contains GLP-1 analogue sequences fused to an antibody Fc fragment, making it more structurally complex than a simple free peptide.
It contains peptide biology, but it is not a simple peptide vial
Dulaglutide is commonly grouped with peptide GLP-1 receptor agonists. Structurally, it is a fusion protein: modified GLP-1 analogue chains are linked to an engineered human IgG4 Fc fragment. “Peptide drug” is useful at category level; “GLP-1/Fc fusion protein” is more precise.
The structure changes quality control
A free synthetic peptide checklist—mass plus HPLC purity—is not enough. Fusion proteins require higher-order structure, glycosylation, aggregation, charge-variant and potency controls alongside primary identity.
| Simple peptide question | Fusion-protein addition |
|---|---|
| Correct sequence? | Correct chain assembly and disulfides? |
| Expected mass? | Expected glycoform distribution? |
| HPLC purity? | Aggregates and charge variants? |
Do not flatten the GLP-1 category
Semaglutide, exenatide and dulaglutide share receptor pharmacology but use different molecular engineering strategies. Those differences explain why one analytical template cannot cover every GLP-1 product.
Verify with primary records
Use the primary paper, current regulator label or lot-linked analytical file for the claim it supports. A search result is a route to evidence, not the evidence itself.